1. Field of The Invention
The present invention relates to a connector housing and particularly to a connector housing which utilizes spacers to prevent pins thereof from becoming short circuited when soldering the connector onto a printed circuit board (PCB).
2. The Prior Art
Connectors are commonly used in coupling electrical signals from one device (for example, a motherboard or a module card used in personal computers) to another device (for example, an edge card which has gold fingers formed on an edge thereof). Connectors have a variety of structures but, each connector generally includes an insulative housing and a plurality of conductive contact pins firmly fixed in the insulative housing.
Each contact pin basically includes a soldering portion at one end thereof, an engaging portion firmly received in a corresponding chamber defined in the insulative housing, and a contact portion for electrically contacting a corresponding gold finger (or contact) fixed in a complementary edge card (or in a male-type connector).
Normally, the soldering portion of each contact pin is a leg projecting from a first face (interface) of the insulative housing of the connector for soldering onto a PCB, while the contacts are formed on a second interface of the insulative housing for electrically contacting the complementary connector or edge card as previously mentioned.
Referring to FIG. 7, two rows of contact pins 6 are connected by a reel carrier tape 63 at respective shoulders 60 thereof. The two rows of contact pins 6 are inserted into and fixed in an insulative housing 50 via an operational machine (not shown), and then the reel carrier tape 63 is detached by the operational machine, thus forming two shoulders 60 on each contact pin 6. Subsequently, another two rows of contact pins are positioned in the same insulative housing 50 using the same method, therefore, a connector 5 with four rows of contact pins is formed.
Referring to FIG. 6, a printed circuit board (PCB) 68 configured with the connectors via holes 62 defined therein undergoes a wave soldering procedure. Thus the solder 61 is soldered to the soldering portion of the contact pins 6 substantially at a position corresponding to the hole 62 of the PCB 68. Most of the contact pins 6 are soldered on the PCB 68 properly such as the rightmost two contact pins 6. However, in some situations, especially when the wave amplitude of the wave soldering procedure is not maintained below a threshold level, the solder passing through two adjacent throughholes 62 is apt to sputter and combine into one integration thus resulting in a short circuit between the related two contact pins. Additionally, due to insufficient preheat of the contact pins 6, the temperature difference between the two sides of the PCB 68 is significant, therefore, when the solder passes through the holes 62 by means of a capillary, the pin portion above the PCB 68 (based on the orientation of the figure) will cause the entering solder to abruptly cool, thus, damaging the surface tension thereof and causing sputtering of the entering solder (the solder above the PCB 68) thereby resulting in a short circuit between adjacent contact pins 6. If a short circuit occurs, trouble shooting and related amendments will increase costs considerably thus reducing profits.
Short circuits are so critical that a new structure is required to eliminate short circuits due to improper wave soldering procedures or other reasons, such as a conductive wire being accidentally positioned between two contact pins when the connector is mounted on the PCB thereby retaining the conductive wire between the contact pins and the PCB.